Sealing machine



y 1945- J. M. HUMPHREY 2,376,253

SEALING MACHINE I Filed April '7, 1944 7 Sheets-Sheet 1 y 15, 1945- J. M. HUMPHREY 2,376,253

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SEALING MACHINE Filed April 7; 1944 '7 Sheets-Sheet '7 NH Z H if ul dum 12H.

Patented May 15, 1945 OFFICE SEALING MACHINE James M. Humphrey, New Richmond, Wis, assignor of ninety per cent to Doughboy Machines, Inc., New Richmond, Wis., a corporation of Wisconsin Application April 7, 1944, Serial No. 530,056

19 Claims.

This invention relates to a sealing machine and more particularly to a portable sealing machine tion with various types of conveyor belts for carrying packages therealong. The sealer may be for use in a production linefor successively sealing the open ends of containers, as for example bags of relatively thin sheet material on the order of wax paper, oiled paper, Cellophane, Pliofilm, or other lightweight and heavyweight, moistureproof, containers in order to hermetically seal the contents for protection until used,

Various sealing machines of this general character have been produced, but these machines have not proven satisfactory due to their cost, unwieldliness, being too massive, requiring too much space, too much material of a'criticalnature, and beinglimited in the character of their work that they could perform; for example, if a change of sealing elements were required considerable time was necessary to do this or to adapt the machine to the particular job or to position the operating parts of the machine at the proper elevation.

It is an object of the invention to provide a simple and inexpensive, portable, sealing machine consisting of few parts and readily applicable to any type of sealing with the least eifort regardless of location, elevation, angularity, presence or absence of heat, and configuration of the sealing element surfaces;

It is a further object of the invention to provide a machine of few inexpensive and simple parts, with easily removable and replaceable sealing elements in the form of cooperating roll-' ers supported in a manner that they may be disposed at any height desired and at any angle, and at the same time, with the course of travel in sealing from left to right or right to left, with means for heating the sealing elements or not as desired and with means for preheating the article prior to its being operated upon by the sealing elements.

An important application of this machine is its adaptability for cooperation with a conveyor over which the sealing elements are disposed for engaging and sealing the upper ends of packages or bags with their contents as they are conveyed by the conveyor. The speed of the sealing rollers is variable for synchronization with the movement of the conveyor belt. This and various other adjustments, such as that ofthe height and angular position of the rollers-with respect to the belt, adjustment of heating in accordance with the material of: the package to be sealed and in accordance with the speed of the sealing rollers and conveyor belt, renders the machine particularly adaptable for application in connecreadily adjusted for packages of different sizes and heights as is frequently necessary in production plants.

Briefly stated the machine consists of selectively heated intermeshing sealing rollers for crimping and sealing together opposite sides of the mouth of a bag or container with the rollers relatively adjustable for accommodating varying thicknesses of'material. vertically and laterally adjustable and are driven by a motor which is reversible so that the direction of the movement of the rollers can be reversed. The above structure makes the machine readily adaptable for use.

Further objects and advantages of my invention will be apparent from the following specification taken' in conjunction with the accompanying drawings, wherein:

Figure 1 is a perspective of a sealing machinein accordance with the invention;

Fig. 2, a side elevation of the sealing machine with parts broken away;

Fig. 3, a horizontal section showing an upper portion of the mechanism;

Fig. 4, a detail perspective view of the sealing mechanism on a larger scale;

Fig. 5, a detail perspective from beneath the sealing rollers;

Fig. 6, a detail vertical section of one of the sealing rollers and adjacent parts;

Fig. 7, a plan view of a flange cover plate for one of the sealing rollers;

Fig. 8, a fragmentary detail illustrating the sealing rollers in elevation with parts broken away;

Fig. 9, a bottom plan view .of the sealing rollers;

Fig. 10, a wiring diagram of the sealing machine driving motor and roller heating elements;

Fig. 11, a fragmentary plan view of the seal- Figs/l3 and 14, side elevations of right and i left guide shoes; I

Fig. 15, a perspective of the under side of a preheater and guide arrangement for directing the upper ends of flexible sheet material containers to the sealing rollers:

The sealing rollers are 7 Fig. 16, an enlarged detail of a modified roller surface known as the checker-cut surface;

Fig. 17, a similar view of the triplex rollers;

Fig. 18, a similar view of a roller with a halfsmooth, half-serrated surface;

Fig. 19, is a perspective of a pair of grooved rollers and a cooperating rod fitting into the grooves for imparting a corresponding configuration to the sheets operated upon; and

Fig. 20, a fragmentary plan view similar to Fig. 11 illustrating a modified guide arrangement.

Referring to the drawings the sealing mechanism of the sealing machine includes a driving motor In with its power transmitting means for rotating sealing rollers II and I2 and an optionally usable container guide I3 for introducing the open top flexible sheet material containers into position to be operated upon by the sealing rollers.

The above members are mounted on a frame or carriage l4 including an upright tubular element l5 slidably mounted on a vertical standard l6 having an apertured base I! by means of which it may be secured in the desired position relative to a belt which carries containers to be sealed by the sealing rollers II and I2. The tubular member of carriage I4 is provided with rearwardly extending bracket elements I! in which a winch or drum i9 is pivotally mounted. This winch is provided with an operating handle for rotating the same for winding and unwinding a cable 2| secured at one end to the drum. This cable extends therefrom and passes over a sheave 22 removably pivoted in the upper end of standard l3 and has its other end secured at the front to the upper end of the vertically adjustable tube element l5.

By this means the elevation of the sealing mechanism with the sealing rollers H and I2 may be adjusted with respect to the conveyor, the upper stretch 23 of which and a container 24 are indicated generally in Fig. 2. Winch I9 is provided with a sprocket or ratchet 25 which is engaged by a pawl 23 whereby the sealing mechanism may be retained in raised position, and for further securing it in such position the tube element I5 is provided with a set screw 23' to engage standard It to thereby retain the sealing mechanism in closer adjustment than that afforded by the ratchet and pawl. The set screw 26' also functions to retain the sealing mechanism at the desired angular position with respect to the conveyor belt on the standard l3.

Standard 16 is provided with a collar 21, having a set screw 28 operable to secure this collar in any desired position on the standard l6, to determinethe normal lowermost position of the sealing mechanism, or if desired, this collar may be positioned directly under the tube member l5 as an additional support when the sealing mechanism has been adjusted to the desired vertical position.

As best'shown in Figs. 1, 2 and 4 the vertically movable sealing mechanism includes the motor in mounted on a bracket 29 extendin from a collar surrounding the tubular element 15 adjacent the upper end thereof. A set screw 33 extends through the collar of the bracket 23 and determines both the elevation and angular position of the motor ID on the tube 15. Below the motor II] are upper and lower forwardly ex-' tending arms 3| and 32 integrally secured to the tubular member l5. A pair of hollow parallel shafts 33 and 34 are vertically Journalled in these arms and carry the sealing rollers II and 12 at their lower ends.

The bearings for the shafts 33 and 34 are preferably of the usual ball or roller bearing type,

and as indicated the lower forward bearing 35 for shaft 34 is adjustable so that sealing roller I2 may be moved toward or away from the sealing roller ii for adjusting the pressure on the work passingbetweeri the rollers. An adjusting screw 36 -in the outer end of the arm 32 engages the bearing 35 whereby the distance between and the pressure on the work or con,- tainer top by sealing rollers Ii and I2 may be varied for suitably sealing the :containers. It will be understood that the upper end of the shaft 34 may be mounted in a similar adjustable bearing or, since the adjustments are slight, the fit of the bearing on the upper end of the shaft may permissibly be loose enough to accommodate for adjustment of the bottom bearing without necessitating like adjustment for the upper end of the shaft. The sealing roller 12 is driven from the sealing .roller H on the shaft 33 upon the upper end of which shaft is fixed a gear 31 driven by a worm 33 on a shaft 39 mounted in bearings 40 and 4| on the tubular element 15 and an intermediate standard 42 fastened to the arms 3! and 32. The shaft 39 is driven through pulleys 43 and 44 and a belt 45 from the motor Ill. The tension of the belt and alignment of the motor may be adjusted by the adjustment of the motor support as provided for by set screws 30 heretofore referred to.

Motor I0 may be of any desired type which is reversible in operation, though preferably, in practice, I employ split phase constant speed alternating current motors of a standard type. In the operation of the sealing machine a speed of 20 feet per minute has been found highly satisfactory for most operations but it is essential to provide for both increased and decreased speeds, as much as for sealing operations ranging from 12 to 50 lineal feet per minute. Such variations of speed of the sealing rollers operated by constant speed motors of the type Just referred to is obtained by employing relatively different sized pulleys to obtain the required speed of the rollers to be in synchronism with the speed of the conveyor 23. Since it is desirable to operate the sealing rollers in either direction such reversal is accomplished by reversing the direction of rotation of motor [0 in the usual manner.

The sealing rollers II and I2 are of the same construction and are best shown in Figs. 5 to 9 illustrating particularly roller l2 which is provided with a thermostat 62. Each sealing roller includes an upper flange element or cover plate 46 integrally secured to its vertical hollow shaft 33 or 34, and the roller itself comprises a cylindrical shell 4] having a cylindrical face 48 provided with cuts or serrations of any desired pattern for mutual cooperation between the rollers.

The lower end or base structure 49 of the roller has a. central bore for engaging its hollow shaft 33 or 34 and a concentric depression 5| in which a washer 52 is positioned and engaged by a stud bolt 53 for removably securing the" sealing roller on its shaft, the interior of the shaft being threaded to receive the upper end of this bolt. The upper edge of the sealing roller 48 is provided with a depression 54 which closely engages a peripheral portion of the collar 46 when the roller is secured in position and a groove 55 in the sealing roller is engageable with 46 are so adjusted as to position and retain the heating element in the bottom portion of the sealingv roller regardless of the depth, since rollers of different heights, face thicknesses, are

employed in connection with. different types of container materials which are to be sealed.

The sealing roller is provided with two small apertures 58 (Fig. 6) through its base 49 affording vents so that air for cooling'may enter from the bottom and pass upward and out through openings in the cover 46. The cover 46 is provided with an aperture 56 for conductors leading to'the terminals 66 of the heating element and with a rectangular aperture 6| in which is mount-- a thermostat 62 having an adjusting arm 63 movable with respect to a scale Lo 1, 2, 3, 4, 5, Hi engraved or stamped on the'cover. mostat being of the usual type, the details thereof need not be set forth, but as shown, it isprovided with the usual conductor terminals 64 connected to the bi-metallic elements which are affected by the heat of the heating element 51 to open and close its switch contacts; not shown. 7 This thermostat is mounted on only one of the sealing rollers; since the roller heating elements .57 are connected in series, the single thermostat trically connected with slip rings 66 carried by the ends of hollow shafts 33 and 34- The upper This ther connected with the motor terminal conductor 11, the other terminal has a separate conductor 18 leading to the motor switch 19, which switch is connected with a conductor 86 to the other terminal of motor l0, and by means of this switch, 19, the operation of the motor is controlled. As shown in Fig. 4 switches and 19 are of the snap mounted in casings 8| on the standards 42.

As shown in Fig. 3, above bracket arm 3l, }a rear end plate 62 projects upwardly as .a rear end closure, and this member is provided with laterbracket arm 3|, adjacent to these slip rings, has I an insulating brush supporting panel 61 with apertures through which spring pressed brushesv 68 are urged into engagement with the slip rings. A lower connected spring fingers element 69 (as shown in the wiring diagram, Fig. 9) and identical upper spring fingers 10 resiliently urge upper and lower carbon brushes 68 against upper and lower slip rings on each of the shafts 33 and 34 to provide electrical connection between stationary and rotatable members. The slip'rings and spring fingersare connected to conductors 12 and s mplicity and the diagram of this portion is dis.- placed to the left of the switches instead of being superimposed thereover. In accordance with "the actual construction the power is supplied by means of a detachable plug connected with a cord or cable 14 leading to a motor junction box'16 directly mounted on the motor I6. As already ally extending studs with wing nuts and washers, 83 thereon for engaging and securing a housing cover 84 as shown in Figs. 1 to 3, over the slip rings 66 and other electrical connections. A rod 85 extends upwardly from a forward portion of arm 3! to supp rt the forward portion of casing 84 in, proper position above the various elements housed thereby. 1

The sealing "rollers H and I2 are housed in casing 86 secured to the under portion of bracket arm 32 and this housing is provided with down-' wardly extending flanges 81 covering thesurfaces of the sealing rollers except the intermediate throat portions on the opposite sides, which are open; Adjacent to these openings are bracket members 88 to which may be secured on either side of the sealing mechanism a guide element 13 of the character presently to be described.

As shown in Figs. 11, 12 and 12a guide I3 is secured to the right hand side of the sealing mechanism for movement of the containers from right to left therethrough. This guide comprises a blade element and a folding shoe 90 which cooperate in maintaining the upper part of the containers in a folded condition as they are carried along by the conveyor and directed into proper position in the throat formed between the cooperating sealing rollers H and [2 as will appear particularly in Figs. 11 and 12a.

In construction blade guide bar 89 consists of a section of channel material 9|, one side wall of which extends beyond the channel construction in both directions to provide the blade or guide' elements 92 so that either extension may operate as a guide, either in the throat of the rollers at the righ side of the sealing mechanism or the throat at the left side. Ihe guide element 92 remote from the throat between the rollers provides a guide or support over which an attendant may initially fold the container stated the power is supplied from the terminals of cable 14 in box 16 to the sealing roller heating elements 51.

For the motor, as indicated, one of the supply terminals of cable 14 is directly sealing r'ollers following which the se ling operation occurs. The other side wall 9 is provided with two pairs of apertures for receiving bolts 94 for securing it either at the right hand or the left hand guide securing bracket member 88. V

In the eventthat the ends of the containers are to be sealed without being folded, the blade or guide bar 92 functions merely to guide the upper edge of the container to the throat of the sealing rollers without performing any other initial operation upon them. However, if the top of the container is to be folded the foldingshoe is also mounted on a guide arm bracket 88 so as to cooperate with the blade 92. This folding shoe v top-end preparatory to its entering the roatJZ etween the "consists of a metal strip having perforations 95 so as to be held in place by bolts 94'within the channel of guide bar 89. This strip is bent towards. the guide blade 92 andthen bent so as to extend substantially parallel therewith with a portion 96 bent downwardly over guide blade '92 so as to extend substantially parallel to this type, from off to on positions and are I the side portions of flanges 81 covering the surface of the sealing rollers II and I2 is substantially closed on one side by the guide element I3. For the protection of the operator a guard element 9'! is secured by screws 98 on the flange element 81 on the other side from the guide. Referring to Fig. 5 it will be seen that this flange is provided with screw perforations 90 on the left side so that in the event the operation of the sealing roller is from left to right the guard element 91 is removed from the right side and placed on the left side as will be apparent.

For such operation from left to right it is essential to place the guide elements I3 on the guide bracket support 80 on the left side and in this case the same guide bar or blade 80 is employed with the opposite guide bar blade extension 02 projecting into the throat between the rollers. For folding operations however the folding shoe 90 has to be replaced by a folding shoe I which is illustrated in Fig. 14. The construction of this shoe is the same as shoe 90 except for the reversal in the formation of the parts.

In this arrangement with the guide elements and folding shoes, the sealing machine is particularly adapted for sealing operations on containers formed of relatively thin materials which are adapted to seal on both surfaces. Thus it is desirable to fold the container tops and seal the containers through such folds. However, if the material is not susceptible of sealing on exterior surfaces such folding operation would be of no use and the folding shoes are omitted and the containers are merely sealed by the sealing of' the adjacent inner surfaces.

For heavy materials, such as laminated materials'and the like, it is necessary to heat the materials before they reach the sealing rollers and in some instances this preheating is all that is necessary, and on some occasions the heating of the rollers is objectionable. In order to provide for heating the sheet material before it reaches the sealing rollers I have provided a preheater comprising a pair of longitudinal heating bars IOI arranged in a casing I02 formedas an extension of the sealing roller casing I03 as shown in Fig. 15. These heatingbars IOI are of such a length that the material while passing between them will he brought to the proper tem- I perature as it emerges into the throat between the sealing rollers. This is accomplished by protemperature of the heating bars may be adjusted and controlled with precision, the casing I01 having similar temperature scale indications thereon as in the case of heating elements 51 and they are likewise connected in series and the temperature of the bars is controlled by the single thermostat, I00. Electric power is supplied to heating elements I05 by means of a power supply cable II 0 which may be connected with the source of power in any desired manner, or as for example, by way of the heat control switch 15. This preheater may be mounted for delivering the containers traveling into the throat of the sealing rollers travelling either from right to left or from left to right in accordance with the direction of operation of the sealing machine.

The sealing rollers of the machine as shown and referred to hereinbefore, have transverse serrations across the interengaging sealing faces. These serrations cooperatively engage each other in such a manner that the driving roller I I serves to drive the driven roller I2. Due to the interdigitating effect of the roller serrations on the sheets, that is, the opposite sides of the bags to be united, are disposed in a zigzag manner, and are thus intimately pressed together, and since the rollers are heated the sheets are hermetically sealed together.

'For certain types of articles to be sealed and consequent sealing operations it is desirable to have more intimate contact of the sheets to be sealed, and likewise the width and location are important. Accordingly sealing rollers of differ-- cut surface characteristics and configurations are employed. For example, checker cut and triplex cut rolls are employed as Well as rolls of different facial widths and numbers of serrations. In fact rolls of all kinds and cuts may be ernployed.

A checker cut roller Ila as indicated in Fig. 16 on a magnified scale has serrations III extending transversely across the peripheral face of the roller and serrations II2 disposed circumferentially of the roller, thus forming in effect small squares simulating those of a checkerboard. A. triplex cut roller is indicated in Fig. 1'7 in which there are three cuttings II3, II I and H5. In other words, in the formation of checker cut rolls serrations II3 are cut across the peripheral surfaces of the rollers and the second cutting H4 is employed for providing serrations circumferentially of the same peripheral surface. With the triplex cut rollers a third cutting operation H5 is accomplished at an angle of 45 relative to the other two, or at any other desired angle. The number of cuts employed is dependent upon the degree of coarseness or fineness necessary in the sealing rollers. The fewer the cuts the eoars- .may be in the form of a band only a fraction of this width, for example more or less, and the remaining unserrated portions In accordingly being of reduced diameter in order not to engage the articles to be sealed, and this serrated band may be disposed between the sides of the rollers in any desired position.

Also, if desired, a plurality of these serrated bands may be employed, and for example as shown in Fig. 19 when two bands of serrations are employed they may be spaced on rollers IIb and I2!) with grooves I20 and I'll respectively between them. The opposed grooves are in contiguous relationship forming a substantial circular opening between the rollers intermediate the serrated surfaces of the same. As shown a stationary pin I22 of a size to freely extend into these opposed grooves is provided which operates on a side of the sheets during the sealing operation. This pin extending backward from the throat functions as a guide member and may be supported on a guide bracket 88 in a similar manner as guide I3 is secured thereto.

In the arrangement for folding and guiding work into the sealing rollers as disclosed in Fig. 11, it is primarily intended for use on certain forms of material where the attendant initially forms a fold of the container over the rearwardly back guide elements. In operation on some materials the folding operation by an attendant may be dispensed with. Thus in accordance with the arrangement shown in Fig. 20 the channel guide element is secured to bracket 88 without the guide shoe 90 as shown in Fig. 11. Casing 86 in this arrangement has an additional bracket 88a extending from flange 81 on the opposite side of the opening, the brackets 88 and 88a directly facing each other in parallel relationship. A uide shoe 1.80 is mounted on bracket 8.8a, this shoe being the shoe I08 illustrated in Fig. 14, and so mounted it extends toward the guide blade 92 which projects into the throat between sealing rollers II and I2, and its end overlaps the sides of blade 92 in the throat. This arrangement affords a guide which receives the work'as it progresses between blade 92 and shoe I and as the edge thereof progresses, the overlapping portion of the shoe performs the folding operation on such light materials as are susceptible of being folded thereby, without the operation by an attendant, or the material may beprogressively drawn therethrough by the sealing rollers themselves.

From the foregoing it will be seen that the sealing machine is extremely compact and portable as compared with many types-of sealing machines heretofore -employed which have been generally massive and cumbersome. The present machine includes a small base flange which may be bolted to the floor or a bench wherever it is desired to employ the machine, and from this base a standard in the form of a tubular pedestal extends upwardly upon which the compact sealing mechanism is mounted. The sealin mechanism is mounted on the standard in a slid-. able'relationship so as to be adjusted as to height and angular position and when adjusted may be locked in position for cooperation with a belt in the production line conveying the articles to be sealed. The sealing mechanism also has such securing and locking elements whereby it may be removed from 'its standard or pedestal and p0 sitioned on another pipe standard as a substitue pedestal. 7 its standard in a vertical position it is also operable in a horizontal or intermediate angular position, the supporting standard therefor naturally being mounted to accommodate such variations ence of heat and pressure, it is also operable-on other materials which may be sealed under other conditions.

It -will be obvious to those skilled in the art that various changes may .be made in the inverttion without departing fromthe spirit and scope thereof and therefore the invention is not lim ited by that which is shown in the drawings and described in the specification but only as indicated in the appended claims.

What is claimed is: 1. A portable sealing machine comprising a base, a standard extending upwardly from said base, a frame vertically and angularly adjustable, a driving motor mounted on said upper support, upright shafts pivotally supported in a pair of said spaced lateral supports below said motor, reduction gearing associated with one of said shafts adapted to be driven by said motor, sealing rollers on the lower ends of said shafts, said rollers having intermeshing surface portions by means of which one of the rollers is driven from the other, heating elements within said sealing rollers, thermostatic means for controlling the heating of the heating elements, a movable bearing element for the shaft of the outermost sealing roller,'and means for adjusting the bearing element with respect to the other shaft whereby the proximity of the rollers and the pressure on an article to be sealed therebetween may be varied to correspond with the character of the arelements within said sealing rollers, thermostatic means for controlling the heating of the heating element's-a movable bearing element for the shaft of one. of the sealing rollers, and means for adjusting said bearing element with respect 3 to the other shaft whereby the proximity of the rollers and the pressure on an article to be sealed. therebetween may be varied to correspond with the character of the article to be engaged by the 'sealing rollers during the sealing operation of While it is illustrated as operating on the machine.

3. A support for' a portablesealing machine comprising a base, a standard extending upwandly from said base, a frame vertically and angularly adjustable onsaid standard, a set collaradjustable in connection with the frame, for limiting the movement of the frame in one direction, means for locking the frame in fixed position on the standard, power means on said frame for raising and lowering the frame with respect to the standard and a series of lateral supports on said frame, sealing rollers carried by said supports and a driving motor for driving the sealing rollers of the sealing machine.

4. A portable machine including a. base, a standard extending upwardly from said base, a frame vertically and angularly jadjustablle on said standard, a set collar adjustable in connection with the frame for limiting the movement of the frame in bneydirection, means for locking the frame in fixed position on the standard, and

power means on said frame for raising and lowering said frame with respect to said standard and a series of lateral supports on said frame, one of said lateral supports being verticall and angularly adjustable with respect to the frame, a

driving motor mounted thereon, driven elements of the machine mounted on other of said lateral supports which are fixedly secured to the frame with respect to said adjustable support, and power transmission means between said driving motor on said adjustable support and the driven elements of the machine on said relatively fixed supports.

5. A machine in accordance with claim 4 including means for supplying electrical energy to the driving motor on the adjustable support and the driven elements of the machine'on the relatively fixed supports, and switches for individually controlling the application of electrical energy to the driving motor and said driven machine elements.

6. A portable sealing machine comprising a supporting standard, vertical and angularly adjustable sealing mechanism on said standard comprising a pair of upright tubular shafts, sealing rollers on the lower ends of said shafts, reduction gearing associated with one of said shafts, a motor for driving one of said shafts through said reduction gearing, said rollers having intermeshing surface portions serving as a driving means between the rollers, heating elements within said rollers, a thermostat on one of the rollers controlling the heating of the heating elements, a pair of contact rings on the upper ends of each of said shafts, conductors extending from the heating elements in the rollers and the thermostat through said shafts to said contact rings, and stationary conductor elements for connecting the heating elements and the thermostat in series with a source of electric power.

7. A portable sealing machine in accordance with claim 6 including a detachable cover mounted above the upper ends of said upright tubular shafts providing a housing for the contact rings and having side walls extending downwardly to provide'a lateral shield over the power transmission reduction gearing.

8. A portable sealing machine comprising a supporting standard, vertical and angularly adjustable sealing mechanism on said standard comprising a pair of upright shafts, sealing rollers on the lower ends of said shafts, reduction gearing associated with on of said shafts, a motor for driving one of said shafts through said reduction gearing, said rollers having intermeshelements and the thermostat in series with a source of electric power.

9. A portable sealing machine comprising a supporting standard, vertical and angularly adiustable sealing mechanism on said standard comprising a pair of upright shafts, sealing rollers on the lower ends of said shafts, reduction gearing associated with one of said shafts, a rev ersible motor for driving one of said shafts through said reduction gearing, said rollers having intermeshing surface portions serving as a driving means between said rollers, heating elements within said rollers, ,a thermostat on one of the rollers controlling the heating of the heating elements, a housing extending over said rollers surrounding said intermeshing surface portions having openings on opposite sides providing access to' the throat portions between the rollers, said housing having means for supporting guide means adjacent to each of said side openings, and guide means adapted to be mounted on one or the other of said supporting means depending on the direction the sealing rollers are to be rotated by the driving motor.

10. A portable sealing machine comprising a supporting standard, vertical and an ularly adjustable sealing mechanism on said standard ing surface portions by means of which the roller on said driven shaft is operable to drive the other roller, heating elements within said sealing rollers, a thermostat on one of the rollers for controlling the heating of the heating elements, a movable bearing element for the shaft of one of the sealing rollers, means for adjusting the bearing element with respect to the other shaft whereby the proximity of the rollers and the pressure on an article to be sealed thereb'etween may be varied to correspond with the character of the article to be engaged by the sealing rollers during the sealing operation of the machine, a pair of contact rings on the upper ends of each of said shafts, conductors extending from the heating elements in the rollers and the thermostat through said shafts to said contact rings, and stationary conductor elements for connecting the heatin comprising a pair of upright shafts, sealing rollers on the lower ends of said shafts, reduction gearing associated with one of said shafts, a reversible motor for driving one of said shafts through said reduction gearing, said rollers having intermeshing surface portions serving as a driving means between said rollers, heating elements within said rollers, a thermostat on one of the rollers controlling the heating of the heating elements, a housing extending over said rollers surrounding said intermeshing surface portions having openings on opposite sides providing access to the throat portions between the rollers, said housing having means for supporting guide means adjacent to each of said side openings, guide means adapted to be mounted on one or the other of said supportingmeans depending on the direction the sealing rollers are to be rotated by the driving motor, said guide means substantially closing the opening through the housing to the throat at one side, and a guard plate adapted to be secured to the housing for closing the other side of the opening to the article receiving throat between the sealing rollers.

11. A portable sealing machine including a pair of cooperating sealing rollers, heating means for the rollers and adjustable thermostatic means for controlling said heating means, a driving motor therefor, speed reduction transmission means between said driving motor and one of said sealing rollers for driving the same, said rollers havin serrated cooperatively intermeshing peripheral surfaces of any desired pattern to provide a drive between the rollers and to impress the surface of an article to be sealed with the pattern of the peripheral surfaces of the rollers during the sealing operation, and means for adjusting the distance between the rollers so as to vary their pressure on an article being sealed thereby.

12. A portable sealing machine including a pair of cooperating sealing rollers, heating means for the rollers and adjustable thermostatic means for controlling said heating means, a driving motor therefor, shafts supporting each of said rollers, speed reduction transmission means between said driving motor and one of said shafts, each of said shafts having a sealing roller cover plate secured thereto, means for securing said rollers on said asvaas's shafts'against said cover plates, interengaging means between the cover plates and rollers for causing them to rotate together, said rollers having serrated cooperatively intermeshing peripheral surfaces of any desired pattern to provide a drive between the rollers and to impress the surface of an article to be sealed with the pattern of the peripheral surfaces of the rollers during the sealing operation, and means for adjusting the distance between the rollers so as to vary their pressure on an article being sealed thereby.

13. A portable sealing machineincluding a pair 'of cooperating sealing rollers, heating means for the rollers and adjustable thermostatic means for controlling said heating means, a driving motor therefor, speed reduction transmission means between'said driving motor and one of said sealing rollers for driving the same said rollers characterized by having serrated cooperatively intermeshing peripheral surfaces of any desired pattern to provide a drive between the rollers and to'impress the surface of an article to be sealed with the pattern of the peripheral surfaces of the ,rollers during the sealing operation, said rollers each having a peripheralgroove intermediate their upper and lower surfaces which grooves cooperate to provide an opening between interengaging surfaces of the rollers, a

stationary pin projecting into the throat between the rollers and the opening provided by said grooves, said pin operating as a guide for the articles entering the sealing rollers and to produce a longitudinal depression in the seal produced on the article by the sealing rollers, and

width of the rollers with the remainder of the width of the rollers of a reduced diameter to provide a drive between the rollers and to impress the surface of an article to be sealed with a seal having a width the same as the width of the serrated part of the peripheral surfaces of the rollers during the sealing operation.

15. A portable sealing machine comprising a supporting standard, vertical and angularly adjustable sealing mechanism on said standard comprising a pair of sealing rollers, reduction gearing associated with one of said rollers, a re,

versible motor for driving one of said rollers through said reduction gearing, said rollers having intermeshing surface portions serving as a driving means between said rollers, heating elements within said rollers, a housing extending over said rollers surrounding said intermeshing surface portions having openings on opposite sides providing access to the throat portions between the rollers, said housing havinga lateral casing extending from one of said side openings and adapted to be projected from the throat either at the right or left side of .the sealing rollers, a pair of laterally extending parallel bars mounted in said laterally extending casing between which an article to be sealed is adapted to pass and be directed into the throat between the sealing rollers, and heating elements in said bars adapted to heat the bars to preheat an article to be sealed prior to its being engaged by the sealing rollers.

16. A portable sealing machine comprising a supporting standard, vertical and angularly adjustable sealing mechanism on said standard comprising a pair of sealing rollers, reduction gearing associated with one of said rollers, a reversible motor for driving, one of said rollers through said reduction gearing, said rollers having intermeshing surface portions serving as a driving means between said rollers, heating elements within said rollers, a housing extending over said rollers surrounding said intermeshing surface portions having openings on, opposite sides providing access to the throat portions between the rollers, said housing having a lateral casing extending from one of said side openings and adapted to be projected from the throat either at the right or left side of the sealing rollers, a pair of lateral extending parallel bars mounted in said laterally extending casing between which an article to be sealed passes and is directed into the throat between the sealing rollers, heating elements in said bars adapted to heat the bars to preheat an article to be sealed prior to its being engaged by the sealing rollers, an adjustable thermostat on one-of the sealing rollers for controlling the heating of the rollers by the heating elements therein, and an adjustable thermostat on one of said bars for controlling the heating of the bars by their heating elements, whereby the heating of the rollers and preheating elements may be individually and differently controlled as. required in the sealing operations.

17. A portable sealing machine including a pair of cooperating sealing rollers, heating means for the rollers and adjustable thermostatic means for controlling said heating means, a driving motor therefor, transmission means between said driving motor and one of said sealing rollers for driving the same, said rollershaving serrated cooperatively intermeshing peripheral surfaces to provide a drive between the rollers and to impress the surface of an article in a sealing operation, a housing extending over said rollers surrounding the serrated surface portions thereof except for openings 'on opposite sides providing access to the throat portions between the rollers.

18. A portable sealing machine including a pair 7 of cooperating sealing rollers, heating means for the rollers and adjustable thermostatic means for controlling said heating means, a driving motor therefor, transmission means between said driving motor and one of said sealing rollers for driving the same, said rollers having serrated cooperatively-intermeshing peripheral surfaces to provide a drive between the rollers and to impress the surface of an article in a sealing operation, a housing extending over said rollers sur-. rounding the serrated surface portions thereof having openingspn opposite sides providing access to the throat portions between the rollers, and guide element supporting brackets mounted one on each side of said housing adjacent to said openings, and a guide element adapted to be motor therefor, transmission means between said driving motor and one of said sealing rollers for driving the same, said rollers having serrated cooperatively intermeshing peripheral surfaces to provide a drive between the rollers and to impress the surface of an article in a sealing operation, a housing extending over said rollers surrounding the serrated surface portions thereof except for openings on opposite sides providing access to the throat portions between the rollers. and guide element supporting brackets mounted one on each side of said housing adjacent to said openings, a guide element adapted to be mounted on one or the other of said guide elements supporting brackets depending on the direction the sealing rollers are to be rotated by the driving motor, said guide element consisting of a longitudinal blade for extending along the approach side of the sealing machine to a point in the throat between the rollers adjacent to their intermeshing positions, and a guide shoe also mounted on said guide element supporting bracket having a portion extending in an overlapping position over the inner portion of the blade' extending into the throat between the sealing rollers.

JAMES M. HUM'PHREY. 

